Excelsior

Does such a thing exist? Or just in my wildest dreams.

Are you thinking the mobile forge to smelt ore on? If so then yes.

and to answer your next question, they are complicated and expensive to make, you have to have gm tinkering, gm carpentry and gm blacksmith to even have a 1 in 3 chance of success. and those of us who can make then, getting the materials is the hard part. I think it takes plat stone, and plat ingots and petrified wood... so when you fail and lose those expensive materials... well.. the cost goes up... usually expect to pay between 200 and 300k for one